QJ-EP8 tail grips use leading or trailing edge control ?

[kgfly]

Calling the Helifreak EP8 brains trust...

I recently had to replace/rebuild my tail. According to the manual that I have, the balls for the tail grips are mounted in the rightmost hole and the grips are oriented with the links on the trailing edge of the tail blades. Someone else said that they should be on the leading edge and showed a photo from their (different) manual.

Here is what my rebuilt tail looks like:

http://lh6.google.com/image/green.kenneth/Rk_XaUtZZgI/AAAAAAAAAJw/rrCYxwOXIZ8/s400/CIMG2530.JPG
http://lh5.google.com/image/green.kenneth/Rk_XIEtZZfI/AAAAAAAAAJo/kIi_qL1MU98/s400/CIMG2532.JPGhttp://lh5.google.com/image/green.kenneth/Rk_XrEtZZhI/AAAAAAAAAJ4/ZBCXwtof18s/s400/CIMG2531.JPG

My questions:

1) Does the EP8v2 SP/EX use leading or trailing edge control on the tail rotor ?

2) What difference will it make ?

3) Why are there two mounting holes for the ball on the grip and which one should be used for trailing edge and for leading edge operation ?

[Pinecone]

I did mine according to the manual for the EX at www.helicopterhobbies.com

I am in Merida, Mex right now, so can't actually check my heli. :(

[kgfly]

Thanks Terry. The SP manual from that site shows trailing edge control while the EX manual shows leading edge control!

It has been suggested that leading edge control makes for a more responsive tail and hence may be desirable for 3D. Since I am a *long* way from 3D, trailing edge control is probably fine, unless someone knows of a problem with the geometry that makes it unwise.

I also read in the EX manual that they recommend NOT using threadlock on the grub screws in the tail assembly. Too late, I already did :oops: I guess I'll have to deal with that when the time comes to replace the tail shaft.

[gorn]

No probs using locktight, just heat it gently with a lighter if you have to remove it.
my tail grips are leading edge.

[Pinecone]

Well, even using Loctite (blue) I had the tail hub screw back out. So I use Loctite.

[kgfly]

Thanks gorn/pinecone, I certainly feel happier with loctite on the grup screws. I always use it on the grub screw in the motor pinion and a while ago I had one of those come out in flight :( I would be scared of losing the tail without Loctite.

[gorn]

No worries mate :)

[Airboss]

leading

[CT4]

I started with trailing edge linkage but did not get a great tail responce so reversed the linkages and it made a big difference,....,if that any help!

[Pinecone]

Thanks gorn/pinecone, I certainly feel happier with loctite on the grup screws. I always use it on the grub screw in the motor pinion and a while ago I had one of those come out in flight :( I would be scared of losing the tail without Loctite.

Recently I had some tail control problems. A nose left drift that could be controlled by some stick input, but for some reason the 401/9254 couldn't deal with it.

Finally one flight it started spining around, with full tail pitch input by the gyro. I found the tail hub to be loose on the shaft, the grub screw having backed out. And yes, I did use blue Loctite on the grub screw.

All was well for a while, and it came back. Finally thought about it, and found that the tail shaft belt pulley was loose. Saem situation, grub screw got loose, even with blue Loctite.

I am thinking that maybe a bit of green (609 or 638 cylindrical assembly locking compound) would be smart on the shaft before assembly, along with blue on the grub screw.